JP4981154B2 - Mobile communication method, mobile station and radio base station - Google Patents

Description

  The present invention relates to a mobile communication method, a mobile station, and a mobile station for receiving downlink data transmitted from a radio base station using downlink radio resources that are fixedly assigned at a predetermined period starting from an allocation start time. It relates to a radio base station.

  The W-CDMA (Wideband-Division Multiple Access) method and the HSDPA (High Speed Downlink Packet Access) successor communication method, that is, the LTE (Long Term Evolution) method is a standardized W-CDMA group based on W-CDMA. The specifications are being developed.

  In the LTE scheme, it is considered that OFDMA is used for the downlink and SC-FDMA (Single-Carrier Frequency Multiple Access) is used for the uplink as a radio access scheme.

  OFDMA is a system in which a frequency band is divided into a plurality of narrow frequency bands (subcarriers) and data is transmitted on each frequency band, and the subcarriers interfere with each other even though they partially overlap on the frequency. By arranging them closely, it is possible to achieve high-speed transmission and increase frequency utilization efficiency.

  SC-FDMA is a transmission method that can reduce interference between terminals by dividing a frequency band and performing transmission using different frequency bands among a plurality of terminals. Since SC-FDMA has a feature that variation in transmission power becomes small, it is possible to realize low power consumption and wide coverage of a terminal.

  The LTE system is a system in which one or two or more physical channels are shared by a plurality of mobile stations for both uplink and downlink.

  A channel shared by a plurality of mobile stations is generally referred to as a shared channel. In the LTE scheme, in the uplink, it is a “Physical Uplink Shared Channel (PUSCH)”, and in the downlink, “ Physical downlink shared channel (PDSCH) ".

  In addition, the shared channel is a “uplink shared channel (UL-SCH)” in the uplink as a transport channel, and a “downlink shared channel (DL-SCH: Downlink) in the downlink. Shared Channel) ”.

  In the communication system using the shared channel as described above, the mobile station UE to which the shared channel is allocated is selected and selected for each subframe (sub-frame) (1 ms in the LTE scheme). It is necessary to signal the allocated mobile station UE to allocate a shared channel.

  The control channel used for this signaling is “physical downlink control channel (PDCCH)” or “downlink L1 / L2 control channel (DL L1 / L2 Control Channel: Downlink L1 //) in the LTE scheme. L2 Control Channel) ".

  Note that the above-described process of selecting which mobile station UE is assigned a shared channel for each subframe is generally called “scheduling”.

  In this case, since the mobile station UE to which a shared channel is dynamically allocated is selected for each subframe, this processing may be referred to as “Dynamic scheduling”.

  Further, the expression “allocating a shared channel” described above may be expressed as “allocating a radio resource for the shared channel”.

  The physical downlink control channel information includes, for example, “downlink scheduling information” and “uplink scheduling grant”.

  In “Downlink Scheduling Information”, for example, downlink resource block (Resource Block) allocation information, UE-ID, number of streams, information on precoding vector (Precoding Vector), data size, regarding downlink shared channel , Information on modulation scheme, HARQ (hybrid automatic repeat request), and the like.

  In addition, “Uplink Scheduling Grant” includes, for example, uplink resource block (Resource Block) allocation information, UE-ID, data size, modulation scheme, uplink transmission power information, Uplink regarding the uplink shared channel. Information on a demodulation reference signal (demodulation reference signal) in MIMO is included.

  Note that the above-described “Downlink Scheduling Information” and “Uplink Scheduling Grant” may be collectively referred to as “Downlink Control Information (DCI)”.

  The mobile station uses the “UE-ID (RNTI)” in the uplink scheduling grant or downlink scheduling to identify whether the uplink scheduling grant or downlink scheduling is transmitted to the mobile station. Do.

  More specifically, CRC bits included in the uplink scheduling grant and downlink scheduling are masked by the RNTI of the transmission destination mobile station.

  The mobile station performs a CRC check using the CRC bit. When the CRC check result is OK, the mobile station determines that an uplink scheduling grant or downlink scheduling is transmitted to the mobile station, and the CRC check result. Is NG, it is determined that no uplink scheduling grant or downlink scheduling is transmitted to the own station.

  The CRC bit is a bit for determining whether the transmitted signal is decoded in error or correctly.

  Therefore, when a certain mobile station receives a signal whose CRC bit is masked by the RNTI of another mobile station, the result of the CRC check is NG even if the signal can actually be received without error.

  The number of bits of the CRC bit and RNTI is, for example, 16 bits.

  In general, a mobile station attempts to decode, for example, 40 uplink scheduling grants or downlink scheduling in one subframe.

  In this case, for example, in about 40 uplink scheduling grants or downlink scheduling, signals actually transmitted to the own station, signals transmitted to other mobile stations, and any signals are included. This includes signals that are not transmitted and contain only noise.

  On the other hand, in “Persistent scheduling” being studied to realize VoIP and the like, the radio base station eNB starts from a subframe (assignment start time) specified by PDCCH (uplink scheduling grant or downlink scheduling information). As described above, uplink or downlink radio resources (PUSCH or PDSCH) are configured to be fixedly assigned to the mobile station at a predetermined period. Note that “Persistent scheduling” may also be referred to as “Semi-Persistent scheduling”.

  The allocation start time is a subframe in which downlink scheduling information is transmitted in the case of downlink, and is an uplink transmission subframe specified by an uplink scheduling grant in the case of uplink. is there. The predetermined period is 20 ms, for example.

  In “Persistent scheduling”, uplink scheduling grant or downlink scheduling information is transmitted via PDCCH only for initial transmission, and uplink scheduling grant or downlink scheduling information is transmitted via PDCCH in subsequent transmissions. Therefore, it is possible to reduce radio resources (overhead) necessary for transmitting the uplink scheduling grant or the downlink scheduling information, and as a result, efficient communication is possible.

  As described above, there are two types of uplink scheduling grant or downlink scheduling information: a case of notifying resource allocation by Dynamic scheduling and a case of notifying resource allocation by Persistent scheduling.

  In this case, the assignment between the dynamic scheduling and the persistent scheduling is identified based on, for example, the uplink scheduling grant or the RNTI set in the downlink scheduling information.

  More specifically, an RNTI for dynamic scheduling and an RNTI for persistent scheduling are defined, and based on the CRC check result, it is identified whether the allocation is based on the dynamic scheduling or the persistent scheduling.

3GPP TS 36.211 (V8.1.0), “Physical Channel and Modulation”, November 2007 3GPP TS36.300 (V8.3.0), “E-UTRA and E-UTRAN Overall description”, November 2007

  As described above, whether the uplink scheduling grant or the downlink scheduling information reports the allocation by the dynamic scheduling or the allocation by the persistent scheduling is identified by the uplink scheduling grant or the downlink scheduling information. This is performed based on RNTI or the like in the link scheduling information.

  Also, the mobile station attempts to decode about 40 uplink scheduling grants or downlink scheduling information within one subframe (within 1 ms).

Here, number of bits of the CRC bit and RNTI are the 16-bit, False Alarm occurs with a probability of ^{1/2 16.} Therefore, when 40 uplink scheduling grants or downlink scheduling information is decoded, the probability that a false alarm will occur is 1/2 ¹⁶ × 40.

  Here, False Alarm means that, although the radio base station has not transmitted an uplink scheduling grant or downlink scheduling information to the mobile station, the mobile station transmits an uplink to itself. An event that determines that a scheduling grant or downlink scheduling information has been transmitted.

  For example, in the case of resource allocation by dynamic scheduling, resource allocation by the uplink scheduling grant and downlink scheduling information is basically limited to the subframe, and thus the influence of the false alarm is small.

  However, in the case of resource allocation by persistent scheduling, an allocation start point is specified by the uplink scheduling grant and downlink scheduling information, and periodically and fixedly starting from the allocation start point. Since radio resources are allocated, the impact of False Alarm is enormous.

  Note that the above False Alarm is not an RNTI but a PDCCH that instructs a fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling” based on a specific 1 bit in the PDCCH, or This is also a problem that can occur in the same way even when it is configured to determine whether the PDCCH is a dynamically assigned PDSCH (downlink radio resource) for normal downlink scheduling.

  Therefore, the present invention has been made in view of the above-described problems, and a stable and efficient mobile communication method by reducing the probability of False Alarm of downlink scheduling information in “Persistent scheduling”. An object of the present invention is to provide a mobile station and a radio base station.

  A first feature of the present invention is mobile communication in which a mobile station receives downlink data transmitted from a radio base station using downlink radio resources that are fixedly assigned at a predetermined period starting from an allocation start time. A method in which the radio base station notifies the mobile station of the predetermined period and information regarding the downlink radio resource, and the mobile station performs fixed allocation from the radio base station. A step B1 of determining the allocation start time when receiving a signal, and receiving the downlink data via the downlink radio resource starting from the allocation start time. In the step B1, the movement The gist is that the station discards the fixed assignment signal when the information about the downlink radio resource and the information notified by the fixed assignment signal are inconsistent.

  That is, the first feature of the present invention is a mobile communication method in which a mobile station receives downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information at a predetermined period. The process A2 for notifying the mobile station of information about the predetermined period and the downlink radio resource, the process B2 of notifying the mobile station of predetermined scheduling information, and the received predetermined scheduling information Starting with a time point determined based on the downlink radio resource allocated by the predetermined scheduling information in the predetermined cycle, and receiving the downlink data, and in step C, the downlink radio The information about the resource and the information notified by the predetermined scheduling information are inconsistent. When, and spirit to discard the predetermined scheduling information.

  In the first aspect of the present invention, the information related to the predetermined period and the downlink radio resource may be notified by an RRC message, and the fixed allocation signal may be notified by downlink control information.

  That is, in the first feature of the present invention, in step A2, information on the predetermined period and the downlink radio resource is notified by an RRC message, and in step B, a downlink control channel is transmitted to the mobile station. The predetermined scheduling information may be transmitted via

  In the first feature of the present invention, the information on the downlink radio resource limits a range of information specified by the fixed allocation signal, and in step B1, the mobile station notifies by the fixed allocation signal. And the information related to the downlink radio resource and the information notified by the fixed allocation signal are inconsistent when the determined information is not included in the range of information specified by the limited fixed allocation signal You may judge.

  That is, in the first feature of the present invention, in step A2, the range of information that can be specified by the predetermined scheduling information is limited by information on the downlink radio resource, and is included in the predetermined scheduling information in step C2. May be determined to be inconsistent with the information regarding the downlink radio resource and the information notified by the predetermined scheduling information. .

In the first aspect of the present invention, the fixed allocation signal, that is, the predetermined scheduling information includes resource block allocation information, modulation scheme, data size, MCS information, information about Redundant Version, transmission format information, and transmission power control information. , At least one of HARQ process information and a new data indicator may be included.

  A second feature of the present invention is a mobile communication method in which a mobile station receives downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information at a predetermined cycle, Based on the step A for notifying the mobile station of information on the predetermined period and the downlink radio resource, the step B for notifying the mobile station of predetermined scheduling information, and the received predetermined scheduling information Using the downlink radio resource allocated by the predetermined scheduling information from the determined time point as a starting point, and transmitting the downlink data, and the information included in the predetermined scheduling information includes: The gist is that the process C is executed when the content matches the contents designated in advance.

  In the second aspect of the present invention, the predetermined scheduling information includes resource block allocation information, modulation scheme, data size, MCS information, information about Redundant Version, transmission format information, transmission power control information, HARQ process information, new It may include at least one of the data indicators.

  A third feature of the present invention is configured to receive downlink data transmitted from a radio base station using downlink radio resources that are fixedly assigned at a predetermined period starting from the allocation start time. A fixed communication information receiving unit configured to receive the predetermined period and information related to the downlink radio resource from the radio base station, and a fixed allocation signal from the radio base station A communication unit configured to determine the allocation start time and receive the downlink data via the downlink radio resource from the allocation start time as a starting point. The unit is configured to discard the fixed assignment signal when the information on the downlink radio resource and the information notified by the fixed assignment signal are inconsistent. The the gist.

  That is, a third feature of the present invention is a mobile station configured to receive downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information at a predetermined period. A receiving unit configured to receive information about the predetermined period and the downlink radio resource from the radio base station, and a time point determined based on the predetermined scheduling information received from the radio base station And a communication unit configured to receive downlink data using downlink radio resources allocated by the predetermined scheduling information at the predetermined period, and the communication unit includes the downlink radio If the information about the resource and the information notified by the predetermined scheduling information are inconsistent, And gist that it is configured to discard a constant scheduling information.

  In the third aspect of the present invention, the information regarding the predetermined period and the downlink radio resource may be notified by an RRC message, and the fixed allocation signal may be notified by downlink control information.

  That is, in the third aspect of the present invention, the receiving unit is configured to receive information on the predetermined period and the downlink radio resource via an RRC message, and the communication unit is configured to perform downlink control. The predetermined scheduling information may be received via a channel.

  Further, in the third feature of the present invention, the communication unit includes the information included in the predetermined scheduling information within a range of information that can be specified by the predetermined scheduling information limited by information related to the downlink radio resource. If not, the information regarding the downlink radio resource may be determined to be inconsistent with the information notified by the predetermined scheduling information.

  Also, in the third feature of the present invention, the fixed allocation signal, that is, the predetermined scheduling information includes resource block allocation information, modulation scheme, data size, MCS information, information about Redundant Version, transmission format information, transmission It may include at least one of power control information, HARQ process information, and a new data indicator.

  A fourth feature of the present invention is a mobile station configured to receive downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information at a predetermined period. A reception unit configured to receive information about the predetermined period and the downlink radio resource from the radio base station, and a time point determined based on the predetermined scheduling information received from the radio base station And a communication unit configured to receive downlink data using downlink radio resources allocated by the predetermined scheduling information at the predetermined period, and the communication unit is configured to receive the predetermined scheduling information according to the predetermined scheduling information. When the notified information matches the contents specified in advance, the downlink data is received. And gist that it is configured to.

  In the fourth aspect of the present invention, the predetermined scheduling information includes resource block allocation information, modulation scheme, data size, MCS information, information about Redundant Version, transmission format information, transmission power control information, HARQ process information, new It may include at least one of the data indicators.

  A fifth feature of the present invention is mobile communication in which a mobile station receives downlink data transmitted from a radio base station using downlink radio resources that are fixedly assigned at a predetermined period starting from the allocation start time. A radio base station used in a system, the mobile station being configured to notify the mobile station of the predetermined period and information related to the downlink radio resource, and the mobile station On the other hand, a fixed allocation signal transmitter configured to transmit a fixed allocation signal and the downlink radio resource starting from the allocation start time determined by the fixed allocation signal A communication unit configured to transmit downlink data, wherein the fixed allocation transmission unit is designated by the fixed allocation signal as information on the downlink radio resource. It is summarized as being configured to notify the information to limit the scope of the information.

  That is, the fifth feature of the present invention is used in a mobile communication system in which a mobile station receives downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information in a predetermined cycle. A first transmitter configured to notify the mobile station of information related to the predetermined period and the downlink radio resource; and predetermined scheduling information for the mobile station And a communication unit configured to transmit downlink data using the downlink radio resource allocated by the predetermined scheduling information in the predetermined period, and a second transmission unit configured to transmit The first transmission unit is designated by the predetermined scheduling information as information on the downlink radio resource. And gist that it is configured to notify the information to limit the scope of the ability information.

  In the fifth aspect of the present invention, the information regarding the predetermined period and the downlink radio resource may be notified by an RRC message, and the fixed allocation signal may be notified by downlink control information.

  That is, in the fifth aspect of the present invention, the first transmission unit is configured to notify information on the predetermined period and the downlink radio resource by an RRC message, and the second transmission unit The predetermined scheduling information may be notified via a link control channel.

  In the fifth aspect of the present invention, the fixed allocation signal, that is, the predetermined scheduling information includes resource block allocation information, modulation scheme, data size, MCS information, information about Redundant Version, transmission format information, and transmission power control. Information, HARQ process information, and a new data indicator may be included.

  In the fifth aspect of the present invention, the first transmission unit may be configured to determine the range based on a data type.

  As described above, according to the present invention, it is possible to reduce the probability of False Alarm of downlink scheduling information in “Persistent scheduling”, and as a result, a stable and efficient mobile communication method. A mobile station and a radio base station can be provided.

FIG. 3 is a functional block diagram of a mobile station according to the first embodiment of the present invention. It is a figure for demonstrating the downlink scheduling information in the mobile communication system which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the scheduling performed in the mobile communication system which concerns on the 1st Embodiment of this invention. FIG. 3 is a functional block diagram of a radio base station according to the first embodiment of the present invention. 3 is a flowchart showing an operation of the mobile station according to the first embodiment of the present invention.

(Configuration of mobile communication system according to the first embodiment of the present invention)
With reference to FIG. 1, the structure of the mobile communication system which concerns on the 1st Embodiment of this invention is demonstrated. In the present embodiment, an LTE mobile communication system is described as an example, but the present invention is also applicable to other mobile communication systems.

  Further, in the mobile communication system according to the present embodiment, the mobile station UE is transmitted from the radio base station eNB using the PDSCH (downlink radio resource) that is fixedly allocated at a predetermined period starting from the allocation start time. Configured to receive downstream data.

  As shown in FIG. 1, the mobile station UE includes a Persistent information receiving unit 61, a Persistent assignment signal receiving unit 62, and a downlink data receiving unit 63.

  The persistent information receiving unit 61 is configured to receive persistent information including the above-described predetermined period and information related to downlink radio resources from the radio base station eNB.

  Further, the persistent information receiving unit 61 is configured to notify the persistent allocation signal receiving unit 62 of information related to the downlink radio resource.

  Specifically, the Persistent information receiving unit 61 is configured to acquire the Persistent information described above based on the RRC message transmitted by the radio base station eNB.

  Here, the information on the downlink radio resource is, for example, a fixed allocation signal (that is, predetermined scheduling information) to be described later, that is, a PDCCH instructing fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling”. This is information for limiting the range of information notified by (downlink scheduling information).

  This will be described in more detail below.

  The information element of PDCCH (downlink scheduling information) instructing the fixed allocation is, for example, information as shown in FIG.

  “Format indicator” is information indicating whether the PDCCH is information for uplink or information for downlink. The information for the downlink is also referred to as simple downlink control information.

  “RB assignment information” is information indicating resource block allocation information related to a downlink signal specified by the PDCCH.

  “MCS information” is information indicating information related to MCS related to a downlink signal specified by the PDCCH. Here, the information on the MCS is information such as a data size, a modulation scheme, and a redundancy version parameter in HARQ, for example.

  “HARQ process information” is information indicating HARQ process information of a downlink signal specified by the PDCCH.

  “New Data Indicator” is information indicating whether the downlink signal specified by the PDCCH is new transmission or retransmission.

  “TPC” is information for transmission power control of an uplink control signal specified by the PDCCH.

  “RNTI / CRC” is a CRC bit masked by “UE-ID (RNTI)”.

  In addition, the information element of PDCCH (downlink scheduling information) mentioned above is an example, and information elements other than the above may be included, or a part of the above information elements may not be included. Good.

  And the information regarding the said downlink radio | wireless resource may be the information for restrict | limiting the range of the information notified by PDCCH (downlink scheduling information) mentioned above so that it may demonstrate below.

  For example, the information on the downlink radio resource may be information for limiting a range of information notified by the “RB assignment information”.

  More specifically, the information on the downlink radio resource may be information for limiting the number of resource blocks and the position of the resource block notified by the “RB assignment information”.

  For example, the information on the downlink radio resource may be information that limits the number of resource blocks notified by the “RB assignment information” to “2” or “3”.

  In this case, when the number of resource blocks notified by the PDCCH (downlink scheduling information) is neither “2” nor “3”, the information on the downlink radio resource and the PDCCH (downlink scheduling information) are notified. Information (RB assignment information) is inconsistent.

  The information on the downlink radio resource may be information that limits the number of resource blocks notified by the “RB assignment information” to “3” or less.

  That is, the information on the downlink radio resource may be information for notifying a maximum value of the number of resource blocks to be notified by the “RB assignment information”.

  In this case, when the number of resource blocks notified by the PDCCH (downlink scheduling information) is not “3” or less, information on the downlink radio resource and information notified by the PDCCH (downlink scheduling information) (RB assignment information) contradicts.

  In the example described above, the information regarding the downlink radio resource is notified of the maximum value of the number of resource blocks notified by the “RB assignment information”, but may be notified of the minimum value instead.

  Alternatively, the information on the downlink radio resource may be notified of both the maximum value and the minimum value of the number of resource blocks notified by the “RB assignment information”.

  For example, for the information on the downlink radio resource, “10” may be notified as the maximum value of the number of resource blocks notified by the “RB assignment information”, and “5” may be notified as the minimum value.

  In this case, when the number of resource blocks notified by the PDCCH (downlink scheduling information) is larger than “10” or smaller than “5”, information on the downlink radio resource and the PDCCH ( Information (RB assignment information) notified by (downlink scheduling information) is inconsistent.

  Further, the information on the downlink radio resource is not limited to the above-described limiting method such as “limit the number of resource blocks” as long as the range of information notified by the “RB assignment information” is limited. The range of information notified by the “RB assignment information” may be limited by the limiting method.

  For example, the information on the downlink radio resource may be information for limiting the position in the frequency direction of the resource block notified by the “RB assignment information”.

  Alternatively, for example, the information on the downlink radio resource may be information notified by the “MCS information”, for example, information for limiting a range such as a modulation scheme and a data size.

  More specifically, the information on the downlink radio resource may be information for limiting the modulation scheme notified by the “MCS information”.

  For example, the information on the downlink radio resource may be information that limits the modulation scheme notified by the “MCS information” to “QPSK”.

  In this case, when the modulation scheme notified by the PDCCH (downlink scheduling information) is other than “QPSK”, for example, when the modulation scheme is “16QAM”, the information on the downlink radio resource and the PDCCH Information (MCS information) notified by (downlink scheduling information) is inconsistent.

  In the above-described example, the information on the downlink radio resource is an example in which the modulation scheme notified by the MCS information is limited to “QPSK”, but is notified by the “MCS information” instead. The modulation method may be limited to “16QAM”, may be limited to “64QAM”, or may be limited to two types of “QPSK” and “16QAM”.

  More specifically, the information regarding the downlink radio resource may be notified of whether or not it is applied for each of the modulation schemes notified by the “MCS information”, “QPSK”, “16QAM”, and “64QAM”.

  Alternatively, for example, the information on the downlink radio resource may be information for limiting the data size notified by the “MCS information”.

  For example, the information on the downlink radio resource may be information that limits the data size notified by the “MCS information” to “320 bits”.

  In this case, when the data size notified by the PDCCH (downlink scheduling information) is other than “320 bits”, for example, when the data size is “512 bits”, the information about the downlink radio resource and Information (MCS information) notified by the PDCCH (downlink scheduling information) is inconsistent.

  The value “320 bits” described above is an example, and a bit number other than “320 bits” may be designated.

  In the above example, one type of data size is specified, but two or more types of data size may be specified.

  That is, for example, the information on the downlink radio resource may be information that limits the data size notified by the “MCS information” to “320 bits” and “640 bits”.

  Alternatively, for example, the information on the downlink radio resource may be information that limits the data size notified by the “MCS information” to “320 bits” or less.

  In this case, when the data size notified by the PDCCH (downlink scheduling information) is larger than “320 bits”, for example, when the data size is “512 bits”, the information about the downlink radio resource and Information (MCS information) notified by the PDCCH (downlink scheduling information) is inconsistent.

  The value “320 bits” described above is an example, and a bit number other than “320 bits” may be designated. In the example described above, the maximum value of the data size is specified, but instead, the minimum value of the data size may be specified.

Alternatively, both the maximum value and the minimum value of the data size may be specified. For example, “640 bits” may be specified as the maximum value of the data size, and “320 bits” may be specified as the minimum value.

  In this case, when the data size notified by the PDCCH (downlink scheduling information) is larger than “640 bits” or smaller than “320 bits”, the information on the downlink radio resource and the PDCCH ( The downlink scheduling information) is inconsistent with the information (MCS information) that is known.

  In the above-described example, the information related to the downlink radio resource is limited to the information notified by the “RB assignment information” or the information notified by the “MCS information”. The information elements other than the above may be restricted in the same manner by the information on the downlink radio resource.

  For example, the information notified by “HARQ process information” may be limited by information on the downlink radio resource.

  For example, when eight HARQ processes are defined and numbered as # 1 to # 8, the number of HARQ processes notified by the “HARQ process information” according to the information on the downlink radio resource is: It may be limited to # 1 and # 2.

  More specifically, the maximum value or the minimum value of the HARQ process number notified by “HARQ process information” may be notified, or the presence or absence of application may be notified regarding each number.

  Further, the above-described “RB assignment information” and “MCS information” are information on resource blocks, modulation schemes, and data sizes, and may be referred to as “information on transmission format”.

  The Persistent assignment signal receiving unit 62 is configured to receive a fixed assignment signal from the radio base station eNB.

  Specifically, the persistent allocation signal reception unit 62 allocates a fixed allocation of PDSCH (downlink radio resource) for “persistent scheduling” transmitted from the radio base station eNB to the local station as a fixed allocation signal. Is configured to receive PDCCH (downlink scheduling information).

  For example, the Persistent allocation signal receiving unit 62, based on the RNTI set in the PDCCH or the like, instructs the PDCCH (downlink radio resource) for fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling” to the own station. It may be configured to determine whether or not (link scheduling information) has been transmitted.

  Further, the persistent allocation signal receiving unit 62 determines whether the PDCCH that dynamically allocates the PDSCH (downlink radio resource) based on the RNTI or the like set in the PDCCH, that is, whether it is downlink scheduling information for dynamic scheduling. It may be configured to determine.

  In addition, as a method of LTE-based persistent scheduling, PDCCH (downlink scheduling information) for instructing fixed allocation of PDSCH (downlink radio resource) for “persistent scheduling” based on one specific bit in PDCCH. If it is defined to determine whether there is PDCCH that dynamically allocates PDSCH (downlink radio resource), that is, downlink scheduling information for dynamic scheduling, the persistent allocation signal receiving unit 62 Is a PDCCH (downlink schedule) that instructs fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling” based on the 1 bit. Packaging information) in which the or, alternatively, PDSCH (downlink radio resource) PDCCH dynamically assigning a, that may be configured to determine a is the one downlink scheduling information for Dynamic scheduling.

  Alternatively, as a method of LTE-based persistent scheduling, a part of information elements in the PDCCH is PDCCH (downlink scheduling information) instructing fixed allocation of PDSCH (downlink radio resource) for “persistent scheduling”. Or the persistent allocation signal receiving unit 62 is defined so as to indicate whether it is PDCCH that dynamically allocates PDSCH (downlink radio resource), that is, downlink scheduling information for dynamic scheduling, A PDCCH (downlink schedule) for instructing fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling” based on a part of information elements in the PDCCH. -Ring information) in which the or, alternatively, PDSCH (downlink radio resource) PDCCH dynamically assigning a, that may be configured to determine a is the one downlink scheduling information for Dynamic scheduling.

  Further, the Persistent assignment signal receiving unit 62 is configured to receive information related to the downlink radio resource from the Persistent information receiving unit 61.

  Here, the information on the downlink radio resource is, as described above, the PDCCH (downlink scheduling) that instructs the fixed allocation of the fixed allocation signal, that is, the PDSCH (downlink radio resource) for “Persistent scheduling”. Information) is information for limiting the range of information notified.

  Then, the persistent allocation signal receiving unit 62 and the PDCCH (downlink) instructing the fixed allocation of the information related to the downlink radio resource and the fixed allocation signal, that is, the PDSCH (downlink radio resource) for “Persistent scheduling”. It is determined whether or not the information notified by the scheduling information) conflicts.

  The persistent allocation signal receiving unit 62 includes information on the downlink radio resource and PDCCH (downlink scheduling information for instructing fixed allocation of the fixed allocation signal, that is, PDSCH (downlink radio resource) for “persistent scheduling”. ), The fixed allocation signal, that is, the PDSCH (downlink radio resource) for “Persistent scheduling”, which has been determined to have been transmitted to the local station, PDCCH (downlink scheduling information) instructing allocation is discarded.

  That is, in such a case, the persistent allocation signal receiving unit 62 notifies the fixed allocation signal, that is, the PDCCH (downlink scheduling information) instructing the fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling”. This information is considered to have not been sent to the local station.

  The persistent allocation signal receiving unit 62 instructs the fixed allocation of the fixed allocation signal, that is, the PDSCH (downlink radio resource) for “Persistent scheduling”, which has not been discarded in the above-described processing. Scheduling information) is provided to the downlink data receiver 63.

  An example of the above-described processing for discarding the fixed allocation signal, that is, the PDCCH (downlink scheduling information) instructing the fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling” is shown below. .

  For example, when the information on the downlink radio resource is information that limits the number of resource blocks notified by the “RB assignment information” to “2” or “3”, the PDCCH (downlink scheduling information) When the number of resource blocks notified by the above is neither “2” nor “3”, the information on the downlink radio resource and the information notified by the PDCCH (downlink scheduling information) (RB assignment information) are inconsistent. Then, the PDCCH (downlink scheduling information) is discarded.

  Alternatively, for example, when the information on the downlink radio resource is information that limits the number of resource blocks notified by the “RB assignment information” to “3” or less, the PDCCH (downlink scheduling information) When the number of notified resource blocks is not “3” or less, for example, when the number of such resource blocks is “5”, notification is made by information on the downlink radio resource and the PDCCH (downlink scheduling information). The received information (RB assignment information) is determined to be inconsistent, and the PDCCH (downlink scheduling information) is discarded.

  Alternatively, for example, when the information on the downlink radio resource is information that limits the number of resource blocks notified by the “RB assignment information” to “10” or less and “5” or more, the PDCCH When the number of resource blocks notified by (downlink scheduling information) is larger than “10” or when the number of such resource blocks is smaller than “5”, for example, the number of such resource blocks is “12”. If it is, it is determined that the information on the downlink radio resource and the information (RB assignment information) notified by the PDCCH (downlink scheduling information) are inconsistent, and the PDCCH (downlink scheduling information) Discard.

  Alternatively, for example, when the information on the downlink radio resource is information for limiting the modulation scheme notified by the “MCS information” to “QPSK” or “16QAM”, the PDCCH (downlink scheduling information) When the notified modulation scheme is neither “QPSK” nor “16QAM”, for example, when the modulation scheme is “64QAM”, information on the downlink radio resource and the PDCCH (downlink scheduling information) ) Is determined to be inconsistent with the information (MCS information) notified by (), and the PDCCH (downlink scheduling information) is discarded.

  Alternatively, for example, when the information on the downlink radio resource is information that limits the data size notified by the “MCS information” to “320 bits”, the information is notified by the PDCCH (downlink scheduling information). When the data size is not “320 bits”, for example, when the data size is “1024 bits”, the information (MCS information) notified by the information on the downlink radio resource and the PDCCH (downlink scheduling information). ) And the PDCCH (downlink scheduling information) is discarded.

  Alternatively, for example, when the information on the downlink radio resource is information that restricts the data size notified by the “MCS information” to “320 bits” or less, the information is notified by the PDCCH (downlink scheduling information). When the data size is not “320 bits” or less, for example, when the data size is “512 bits”, information about the downlink radio resource and information notified by the PDCCH (downlink scheduling information) ( It is determined that there is a contradiction with MCS information), and the PDCCH (downlink scheduling information) is discarded.

  Alternatively, for example, when the information on the downlink radio resource is information that restricts the data size notified by the “MCS information” to “640 bits” or less and “320 bits” or more, the PDCCH ( When the data size notified by the downlink scheduling information) is larger than “640 bits”, or when the data size is smaller than “320 bits”, for example, when the data size is “1024 bits”. Determines that the information on the downlink radio resource and the information (MCS information) notified by the PDCCH (downlink scheduling information) are inconsistent, and discards the PDCCH (downlink scheduling information).

  Alternatively, for example, when the information on the downlink radio resource is information that restricts the number of HARQ process notified by the “HARQ process information” to # 1 and # 2, the PDCCH (downlink scheduling information) If the HARQ process number notified by is not # 1 or # 2, for example, if the number is # 3, it is notified by information on the downlink radio resource and the PDCCH (downlink scheduling information) It is determined that the information (HARQ process information) is inconsistent, and the PDCCH (downlink scheduling information) is discarded.

  In the above-described example, the persistent allocation signal receiving unit 62 instructs information regarding the downlink radio resource and the fixed allocation of the fixed allocation signal, that is, PDSCH (downlink radio resource) for “persistent scheduling”. When it is determined whether or not there is a contradiction with information notified by PDCCH (downlink scheduling information) to be performed, but instead, it is determined whether or not there is a contradiction other than the above, and it is determined that such a contradiction exists In addition, the fixed allocation signal, that is, the PDCCH (downlink scheduling information) instructing the fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling” may be discarded.

  For example, the persistent assignment signal receiving unit 62 uses the fixed assignment signal, that is, “persistent scheduling” when the maximum receivable data size is “10000 bits” as the capability (capability) of the mobile station. If it is instructed to receive a downlink signal having a data size of “20000 bits” by PDCCH (downlink scheduling information) instructing fixed allocation of PDSCH (downlink radio resource), the fixed May be discarded, that is, PDCCH (downlink scheduling information) instructing fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling”.

  Alternatively, in general, the fixed allocation signal, that is, the PDCCH (downlink scheduling information) instructing the fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling” has no meaningful bit pattern as information. Exists.

  Therefore, the persistent allocation signal receiving unit 62 is a part of the fixed allocation signal, that is, a bit of PDCCH (downlink scheduling information) instructing the fixed allocation of the PDSCH (downlink radio resource) for “persistent scheduling”. When the pattern has no meaning as information, the fixed allocation signal, that is, PDCCH (downlink scheduling information) instructing fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling” is discarded. May be.

  Note that the expression “a bit pattern has no meaning as information” may be expressed in other words as a bit pattern that should not be notified.

  In this case, the persistent assignment signal receiving unit 62 performs the fixed assignment of the fixed assignment signal, that is, the PDSCH (downlink radio resource) for “persistent scheduling”, regardless of the information on the downlink radio resource. It may be determined whether a part of the bit pattern of the indicated PDCCH (downlink scheduling information) has meaning as information.

  Alternatively, the persistent allocation signal receiving unit 62 performs the fixed allocation of the above-described fixed allocation signal, that is, PDSCH (downlink radio resource) for “Persistent scheduling”, when there is no information regarding the downlink radio resource. It may be determined whether a part of the bit pattern of PDCCH (downlink scheduling information) instructing is meaningful as information.

  Here, an example of the above-described “bit pattern that should not be notified” will be described.

  For example, in the fixed assignment signal, when it is defined that the value of the RB number indicated by “RB assignment information” in FIG. 2 is always “10” or less, the number of RBs indicated by the “RB assignment information”. The bit pattern indicating a value larger than “10” is a bit pattern that should not be notified.

  That is, when the value of the number of RBs indicated by “RB assignment information” in the fixed allocation signal is larger than “10”, the mobile station UE discards the fixed allocation signal.

  Alternatively, for example, in the fixed allocation signal, when the data size value indicated by “MCS information” in FIG. 2 is always defined to be “1000” or less, the data size indicated by the “MCS information” As a bit pattern indicating a value larger than “1000”, the bit pattern should not be notified.

  That is, the mobile station UE discards the fixed assignment signal when the value of the data size indicated by “MCS information” in the fixed assignment signal is larger than “1000”.

  Note that “when the value of the data size indicated by“ MCS information ”is larger than“ 1000 ”” means, for example, that some bits of the “MCS information” are not a predetermined value. Good. For example, when the data size is defined by a 4-digit binary number (hereinafter referred to as “abcd”; the first “a” is “Most Significant bit”), the data size is expressed in decimal. Then:

(Decimal data ^{size) = 2 3 × a + 2} 2 × b + 2 1 × c +2 0 × d
Here, when “a” that is “Most Significant bit” is not “0”, that is, when it is “1”, the data size is “8” or more.

  That is, the mobile station UE may discard the fixed assignment signal when some of the bits of “MCS information” in the fixed assignment signal are not a predetermined value.

  Furthermore, the mobile station UE determines that the “Most significant bit” of the “MCS information” in the fixed assignment signal is not a predetermined value (for example, in the above example, the “Most significant bit” is not “0”). Or when the value of a predetermined number of bits consecutive from “Most significant bit” is not a predetermined value (for example, in the above example, “the value of two consecutive bits is not a predetermined value) Assuming that there is no “when”, the values of both “a” and “b” are not “0”), the fixed allocation signal may be discarded.

  The same processing may be applied when the “MCS information” notifies both of the data size and the modulation method.

  Alternatively, for example, in the case of the fixed allocation signal, when the modulation scheme indicated by “MCS information” in FIG. 2 is always defined as “QPSK”, the modulation scheme indicated by the “MCS information” is “ A bit pattern indicating “16QAM” or “64QAM” is a bit pattern that should not be notified.

  That is, when the modulation scheme indicated by “MCS information” in the fixed assignment signal is not “QPSK”, the mobile station UE discards the fixed assignment signal.

  Alternatively, for example, since the fixed assignment signal is basically a signal for instructing new transmission, a bit pattern that specifies a modulation method at the time of retransmission in the “MCS information” is a bit that should not be notified. It becomes a pattern.

  That is, the mobile station UE discards the fixed assignment signal when the “MCS information” in the fixed assignment signal is a bit pattern that specifies a modulation method at the time of retransmission.

  Alternatively, for example, in the fixed assignment signal, when it is defined that “1” is always set as the value of “TPC” in FIG. 2, “0” as the value of “TPC”. Is a bit pattern that should not be notified.

  That is, the mobile station UE discards the fixed allocation signal when the value of “TPC” in the fixed allocation signal is “0”.

  In the example described above, the number of bits of “TPC” is “1”, but may be a value other than “1”, for example, “2” or “3”. For example, in the case where the number of bits of “TPC” is “2” and it is defined that “11” is always set as the value of “TPC”, “10”, “01”, “00” is a bit pattern that should not be notified.

  Alternatively, for example, in the fixed assignment signal, when it is defined that “111” is always set as the value of “HARQ process information” in FIG. 2, as the value of “HARQ process information”, Bit patterns other than “111” are bit patterns that should not be notified.

  That is, the mobile station UE discards the fixed assignment signal when the value of “HARQ process information” in the fixed assignment signal is other than “111”.

  In the example described above, the number of bits of “HARQ process information” is “3”, but may be a value other than “3”, for example, “2” or “4”.

  Alternatively, for example, when it is defined that “11” is always set as the value of “Redundancy Version” included in “MCS information” of FIG. 2 in the fixed allocation signal, the “Redundancy Version” is defined. A bit pattern other than “11” as a value of “” is a bit pattern that should not be notified.

  That is, the mobile station UE discards the fixed assignment signal when the value of “Redundancy Version” in the fixed assignment signal is other than “11”.

  In the example described above, the number of bits of “Redundancy Version” is “2”, but may be a value other than “2”, for example, “1” or “3”.

  Alternatively, for example, in the fixed allocation signal, when it is defined that “1” is always set as the value of “New Data Indicator” in FIG. 2, the value of “New Data Indicator” is “0” is a bit pattern that should not be notified.

  That is, the mobile station UE discards the fixed assignment signal when the value of “New Data Indicator” in the fixed assignment signal is “0”.

  Alternatively, the mobile station UE may identify the above-described “bit pattern that should not be notified” based on information in the fixed assignment signal received in the past.

  For example, when the data size indicated by “MCS information” in the fixed allocation signal received in the past is always “320 bits”, the mobile station UE sets a bit pattern indicating a data size other than “320 bits”, It may be regarded as a bit pattern that should not be notified.

  In consideration of the occurrence of “False Alarm” in a state where a correct fixed allocation signal has never been received in the past, for example, the mobile station UE fixes the same data size at least “three times” in the past. When a general allocation signal is received, a bit pattern indicating a data size other than the data size may be regarded as a bit pattern that should not be notified.

  Alternatively, the mobile station UE should not be notified of a bit pattern indicating a data size other than the data size when receiving a fixed allocation signal having the same data size continuously “three times” or more in the past. It may be regarded as a bit pattern.

  In the example described above, the number “320 bits” and the number “three times” are merely examples, and values other than those described above may be used.

  Note that a plurality of processes may be simultaneously applied to the process of discarding the PDCCH (downlink scheduling) instructing the fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling” described above.

  That is, a process of discarding a plurality of PDCCHs instructing the fixed assignment is performed, and when it is determined that the PDCCH is discarded in at least one process, a process of discarding the PDCCH is performed. May be.

  The downlink data receiving unit 63 is configured to receive downlink data transmitted via the PDSCH (downlink radio resource) allocated by the PDCCH.

Specifically, the downlink data receiving unit 63 receives, from the persistent allocation signal receiving unit 62, the above-described persistent allocation signal (fixed allocation signal), that is, the fixed allocation of PDSCH (downlink radio resource) for “persistent scheduling”. When the PDCCH (downlink scheduling information) instructing the PDCCH is received, the subframe in which the PDCCH is transmitted is determined as the above-mentioned “allocation start time”, and the above “predetermined period” ”Is fixedly received via the PDSCH (downlink radio resource) for“ Persistent scheduling ”.

  In the example of FIG. 3, since the persistent allocation signal receiving unit 62 receives the above-described persistent allocation signal via the PDCCH in subframe # 3, the downlink data receiving unit 63 transmits the transmission subframe # in which the PDCCH is transmitted. 3 is configured to receive downlink data via a PDSCH (downlink radio resource) mapped to a resource block (a set of subcarriers) in the network.

  Also, the downlink data receiving unit 63 starts PDSCH (downlink radio resource) mapped to the resource block (set of subcarriers) specified by the PDCCH with a period of 20 ms (predetermined period) starting from subframe # 3. Via the network, and is configured to receive downlink data.

  That is, the downlink data reception unit 63 transmits the PDSCH (downlink radio resource) mapped to the resource block (set of subcarriers) specified by the PDCCH in subframes # 3, # 23, # 43,. , Configured to receive downlink data.

  On the other hand, the radio base station eNB according to the present invention is configured to notify the mobile station UE of information on the above-described predetermined period and downlink radio resource.

  Since the description regarding the information regarding this downlink radio | wireless resource is the same as the description in the mobile station UE, it abbreviate | omits.

  As illustrated in FIG. 4, the radio base station eNB includes a Persistent information transmission unit 71, a Persistent assignment signal transmission unit 72, and a downlink data transmission unit 73.

  The Persistent information transmission unit 71 is configured to transmit Persistent information (fixed communication information) including the above-described predetermined period and information related to downlink radio resources to the mobile station UE.

  Specifically, the Persistent information transmission unit 71 is configured to notify the mobile station UE of the Persistent information using an RRC message.

  Here, the information on the downlink radio resource is notified by, for example, a fixed allocation signal, that is, a PDCCH (downlink scheduling information) instructing a fixed allocation of a PDSCH (downlink radio resource) for “Persistent scheduling”. This is information for limiting the range of information to be stored.

  In addition, since the description of the information regarding a downlink radio | wireless resource is the same as the description in the mobile station UE, it abbreviate | omits.

  Further, the persistent information transmission unit 71 may set information regarding the downlink radio resource based on the data type.

  For example, when the data type is VoIP, the persistent information transmission unit 71 restricts the number of resource blocks notified of the information on the downlink radio resource by the “RB assignment information” to “3” or less. When the data type is streaming, the information on the downlink radio resource is set to information that limits the number of resource blocks notified by the “RB assignment information” to “10” or less. May be.

  Alternatively, the persistent information transmission unit 71 sets the information on the downlink radio resource to information that restricts the modulation scheme notified by the “MCS information” to “QPSK” when the data type is VoIP. When the data type is streaming, the information on the downlink radio resource may be set to information that restricts the modulation scheme notified by the “MCS information” to “QPSK” or “16QAM”.

  Alternatively, when the data type is VoIP, the persistent information transmission unit 71 sets the information on the downlink radio resource to information that restricts the data size notified by the “MCS information” to “320 bits”. However, when the data type is streaming, the information on the downlink radio resource may be set to information that restricts the data size notified by the “MCS information” to “640 bits”.

  That is, how the information notified by the fixed allocation signal, that is, the PDCCH (downlink scheduling information) instructing the fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling” is limited. May be determined according to the data type of data to which resources are allocated by persistent scheduling.

  The “data type” described above may be rephrased as “service type”. That is, the “service type” indicates a type of service that transmits a packet, and may include, for example, a VoIP service, a voice service, a streaming service, an FTP (File Transfer Protocol) service, and the like.

  In the above-described example, the persistent information transmission unit 21 sets information on the downlink radio resource based on “data type”, but instead, “contract type”, “logical channel type”, “cell type”, Information on the downlink radio resource may be set based on the “priority type”.

  The “contract type” indicates the type of contract to which the user of the mobile station UE has subscribed, and includes, for example, a Low Class contract, a High Class contract, a fixed charge contract, a pay-per-use contract, and the like.

  The “cell type” is a cell operation mode, and can be indoor, outdoor, urban, or countryside.

  “Logical channel type” is a type of logical channel such as Dedicated Control Channel (DCCH) or Dedicated Traffic Channel (DTCH). A plurality of logical channels may be further defined in the DCCH and DTCH.

  Here, “Radio Bearer” means a bearer that transmits data, and is defined on a one-to-one basis with respect to a logical channel for transmission, and as a result, is almost synonymous with a logical channel.

  The “priority type” is a class for classifying priorities related to transmission of downlink and uplink data. For example, data of the first priority class is data of the second priority class. It is transmitted with priority over.

  The “priority type” is bundled with the Logical Channel and may be referred to as “Logical Channel Priority”. Alternatively, the “priority type” may be defined as “Priority Class”.

  The Persistent allocation signal transmitter 72 is configured to transmit a fixed allocation signal to the mobile station UE.

  Specifically, the persistent allocation signal transmission unit 72 instructs the mobile station UE to perform fixed allocation of PDSCH (downlink radio resource) for “persistent scheduling” as a fixed allocation signal (downlink). Scheduling information).

  In addition, as described above, the persistent assignment signal transmission unit 72 is defined as “1” is always set as the value of “TPC (see FIG. 2)” in the fixed assignment signal. Alternatively, “1” may always be set as the value of “TPC”.

  Alternatively, for example, the persistent assignment signal transmission unit 72 is defined as “111” is always set as the value of “HARQ process information (see FIG. 2)” in the fixed assignment signal as described above. In such a case, “111” may always be set as the value of the “HARQ process information”.

  Alternatively, for example, as described above, the persistent assignment signal transmission unit 72 is defined as “11” being always set as the value of “Redundancy Version” in the fixed assignment signal. “11” may always be set as the value of the “Redundancy Version”.

  Alternatively, for example, as described above, the persistent assignment signal transmission unit 72 defines that “1” is always set as the value of “New Data Indicator (see FIG. 2)” in the fixed assignment signal. In such a case, “1” may always be set as the value of the “New Data Indicator”.

  The downlink data transmission unit 73 is configured to transmit downlink data transmitted via a PDSCH (downlink radio resource) allocated by the PDCCH.

  Specifically, when the persistent allocation signal (fixed allocation signal) is transmitted by the persistent allocation signal transmission unit 72, the downlink data transmission unit 73 transmits the subframe in which the PDCCH is transmitted to the “allocation” described above. It is determined as a “start time”, and is configured to transmit downlink data via the PDSCH (downlink radio resource) for “Persistent scheduling” fixedly at the “predetermined period” with the “allocation start time” as the start Has been.

(Operation of the mobile communication system according to the first embodiment of the present invention)
With reference to FIG. 5, the operation of the mobile communication system according to the first embodiment of the present invention will be described.

  As shown in FIG. 5, in step S201, the mobile station UE receives Persistent information including the above-described predetermined period and information on downlink radio resources from the radio base station eNB by an RRC message or the like.

  The information on the downlink radio resource is notified by, for example, a fixed allocation signal, that is, a PDCCH (downlink scheduling information) instructing a fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling”. This is information for limiting the range of information.

  The description of the information related to the downlink radio resource is the same as the description in the mobile station UE, and will be omitted.

  In step S202, the mobile station UE receives a Persistent assignment signal (fixed assignment signal) transmitted via the PDCCH by the radio base station eNB.

  More specifically, the mobile station UE gives a PDCCH (downlink scheduling information) instructing a fixed allocation of PDSCH (downlink radio resource) for “persistent scheduling” as a fixed allocation signal from the radio base station eNB. Receive.

  In step S203, the mobile station UE and the PDCCH (downlink scheduling) instructing the fixed allocation of the downlink radio resource and the fixed allocation signal, that is, PDSCH (downlink radio resource) for “Persistent scheduling”. It is determined whether or not the information notified by (information) is inconsistent.

  Note that the details of the above-described determination as to whether or not there is a contradiction are the same as those described in the mobile station UE, and are therefore omitted.

  The mobile station UE is notified by information related to the downlink radio resource and the fixed allocation signal, that is, PDCCH (downlink scheduling information) instructing fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling”. If it is determined that there is a contradiction with the information to be performed (step S203: YES), the operation proceeds to step S204.

  In step S204, the mobile station UE discards the fixed allocation signal, that is, PDCCH (downlink scheduling information) instructing the fixed allocation of PDSCH (downlink radio resource) for “Persistent scheduling”.

  That is, the mobile station UE is notified of the fixed allocation signal, that is, information notified by the PDCCH (downlink scheduling information) instructing the fixed allocation of the PDSCH (downlink radio resource) for “Persistent scheduling”: BR> It is considered not to have been sent to the station.

  In step S205, the mobile station UE receives the above-described persistent assignment signal (fixed assignment signal), that is, PDCCH (downlink scheduling information) instructing fixed assignment of PDSCH (downlink radio resource) for “Persistent scheduling”. The transmitted subframe is determined as the above-described allocation start time, and downlink data reception via the PDSCH (downlink radio resource) for “Persistent scheduling” is fixed at the above-described predetermined period from the allocation start time. Start.

  That is, in such a case, the mobile station UE receives downlink data via the PDSCH (downlink radio resource) for persistent scheduling until the PDSCH (downlink radio resource) for “Persistent scheduling” is released.

(Operations and effects of the mobile communication system according to the first embodiment of the present invention)
As described above, probability of the occurrence of the False Alarm for one PDCCH (uplink scheduling grant or the downlink scheduling information) is ^{1/2 16.}

In general, since the mobile station UE attempts to decode about 40 PDCCHs in one subframe, the total False Alarm probability is calculated as 40 × 1/2 ¹⁶ = 0.0006.

  Here, the above-described False Alarm is an event in which the mobile station UE determines that the PDCCH is accidentally transmitted to the local station even though the PDCCH is not transmitted to the local station. It is highly possible that the information is random information.

  Therefore, as described above, when the mobile station UE has a limit on the range of information in the PDCCH and receives a PDCCH having information other than the above limit, by performing a process of discarding the PDCCH, The probability of the False Alarm can be greatly reduced.

For example, it is assumed that the number of bits other than CRC in the PDCCH is “24 bits”, and the range of “12 bits” is limited. In order to simplify the calculation, it is assumed that the bit pattern of the “12 bits” is limited to one. In this case, as described above, when the mobile station UE limits the range of information in the PDCCH, and receives a PDCCH having information other than the above-mentioned limit, the process of discarding the PDCCH causes the False The probability of Alarm is
It is calculated as ^{40 × 1/2 16 × 2} 12/2 24 = 1.5 × 10 -7, greatly reduced.

  That is, according to the mobile communication system according to the first embodiment of the present invention, it is possible to reduce the probability of PALCH (False Alarm of downlink scheduling information) notifying resource allocation for persistent scheduling. A stable and efficient mobile communication method, mobile station, and radio base station can be provided.

(Example of change)
The operations of the mobile station UE and the radio base station eNB described above may be implemented by hardware, may be implemented by a software module executed by a processor, or may be implemented by a combination of both. .

  The software module includes a RAM (Random Access Memory), a flash memory, a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electronically Erasable and Programmable ROM, a Hard Disk, a Registered ROM, a Hard Disk Alternatively, it may be provided in a storage medium of an arbitrary format such as a CD-ROM.

  Such a storage medium is connected to the processor so that the processor can read and write information from and to the storage medium. Further, such a storage medium may be integrated in the processor. Such a storage medium and processor may be provided in the ASIC. Such an ASIC may be provided in the mobile station UE or the radio base station eNB. Further, the storage medium and the processor may be provided as a discrete component in the mobile station UE or the radio base station eNB.

  Although the present invention has been described in detail using the above-described embodiments, it is obvious to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be implemented as modified and changed modes without departing from the spirit and scope of the present invention defined by the description of the scope of claims. Therefore, the description of the present specification is for illustrative purposes and does not have any limiting meaning to the present invention.

  UE ... mobile station 61 ... persistent information receiving unit 62 ... persistent allocation signal receiving unit 63 ... downlink data receiving unit eNB ... radio base station 71 ... persistent information transmitting unit 72 ... persistent allocation signal transmitting unit 73 ... downlink data transmitting unit

Claims (3)

A mobile communication method in which a mobile station receives downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information in a predetermined cycle,
Step A for notifying the mobile station of the predetermined period;
Step B for notifying the mobile station of predetermined scheduling information;
Starting with a time determined based on the received predetermined scheduling information as a starting point, and using a downlink radio resource allocated by the predetermined scheduling information in the predetermined period, and a step C of transmitting downlink data,
The predetermined scheduling information is discarded when the information included in the predetermined scheduling information does not match at least one of predefined “MCS information”, “TPC”, and “HARQ process information”. Mobile communication method. A mobile communication method in which a mobile station receives downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information in a predetermined cycle,
Step A for notifying the mobile station of the predetermined period;
Step B for notifying the mobile station of predetermined scheduling information;
Starting with a time point determined based on the received predetermined scheduling information as a starting point and receiving downlink data using the downlink radio resource allocated by the predetermined scheduling information at the predetermined period,
The mobile communication method, wherein the step C is executed when information included in the predetermined scheduling information matches a predefined “MCS information” and “HARQ process information”. A mobile station configured to receive downlink data transmitted from a radio base station using downlink radio resources allocated by predetermined scheduling information in a predetermined cycle,
A receiving unit configured to receive the predetermined period from the radio base station;
Starting from the time determined based on the predetermined scheduling information received from the radio base station, the downlink data is received in the predetermined cycle using the downlink radio resource allocated by the predetermined scheduling information. A communication unit,
The communication unit discards the predetermined scheduling information when information included in the predetermined scheduling information does not match at least one of the predefined “MCS information”, “TPC”, and “HARQ process information”. A mobile station that is configured as described above.

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